Scientific American: Algae Found to Produce Potential Neurotoxin

Science & Technology at Scientific American.com: Algae Found to Produce Potential Neurotoxin
April 05, 2005
Algae Found to Produce Potential Neurotoxin

A variety of types of blue-green algae all produce the same molecule, a potential neurotoxin, a new report suggests. The results, published online this week by the Proceedings of the National Academy of Sciences, represent the first time that unrelated species of cyanobacteria have been found to produce the same potentially hazardous substance.
Cyanobacteria can produce a wide range of molecules that are harmful to humans, but which species generate which compounds has so far been quite unpredictable. Paul Alan Cox of the National Tropical Botanical Garden in Hawaii and his colleagues studied five different morphological sections of cyanobacteria, as well as cyanobacterial symbionts taken from lichen and other plant species. They discovered that 95 percent of all genera of cyanobacteria produce a molecule identified as BMAA, a suspected neurotoxin that has been recently detected in the brains of some Alzheimer's sufferers. The amount of BMAA manufactured by the algal samples varied widely. The scientists thus posit that BMAA production and storage is a function of either growth conditions or life cycle stages of the bacteria.

Because of the widespread nature of cyanobacteria, the researchers suggest that it might be wise to monitor levels of BMAA in drinking water sources that contain cyanobacterial blooms. They note: "The ubiquity of cyanobacteria in terrestrial, as well as freshwater, brackish and marine environments, suggests a potential for widespread human exposure." --Sarah Graham

GrokEnergy: Using seaweed to reduce greenhouse gases and make biofuel

GrokEnergy: Using seaweed to reduce greenhouse gases and make biofuel
Using seaweed to reduce greenhouse gases and make biofuel. This is really interesting. A group of Japanese scientists is proposing to plant vast fields of seaweed to soak up greenhouse gases, then harvest the seaweed and process it into a biofuel. Check it out.
***
Seaweed to breathe new life into fight against global warming
By Leo Lewis in Tokyo

Huge water-borne farms can turn the tide against increasing greenhouse gases

REMEMBER the names sargassum and Sostera marina: if a group of Japanese scientists is to be believed, the fate of humanity may rest on colossal floating islands of the stuff.

The team envisages 100 vast nets full of quick-growing seaweed, each measuring six miles by six miles, floating off the northeast coast of Japan.

The seaweed in each net, growing to a weight of 270,000 tonnes a year, will absorb prodigious quantities of greenhouse gases and convert them to oxygen before being harvested 12 months later as a rich source of biomass energy.

If a pilot version of the project indicates that the idea is viable, and sufficient funding can be found, the concept of fighting global warming through giant seaweed farms across the world’s oceans could be included in the upcoming revision to the Kyoto Protocol.

The Japanese Ministry of Economy, Trade and Industry mentioned carbon dioxide absorption by seaweed in its Technology Roadmap for 2005. The project is led by Masahiro Notoya, a world expert on seaweed from the Tokyo University of Marine Science and Technology. Dr Notoya believes that Sostera marina and sargassum, herded to the right parts of the ocean, will grow up to 40ft every year, absorbing about 36 tonnes of carbon dioxide in the process. Those seaweeds are also popular fare for a variety of fish whose stocks have dwindled.

Working with Dr Notoya are scientists at the Mitsubishi Research Institute and Tokyo University. Mitsubishi Heavy Industries, Mitsubishi Electronics, Toshiba and NEC are among a large group of companies involved. The Japanese Government has provided a small grant and is expected to give more when a pilot version of the giant seaweed farm opens next year.

Another obstacle is finding enough empty sea to accommodate the vast farms. “It’s the main problem we face — particularly because of the two strong currents that run off the Japanese archipelago, but also because there are only certain parts of the ocean where seaweed grows well,” Dr Notoya said.

The nets will be equipped with a technology allowing them be tracked by global positioning satellites, so that they could be dragged back into position should they stray into a shipping lane.

Dr Notoya’s team will present its proposal this month to the Japan Research Industries Association and will attempt to convince industry leaders that the idea is worth the 570 billion yen (£2.8 billion) needed to implement it on the grand scale necessary.

“It’s actually thanks to seaweed that we’re here at all,” Dr Notoya said. “When the world was young, it was the little blue-green algae and other seaweeds that, over the years, converted so much of the carbon dioxide in the air into oxygen and eventually pushed it up to the levels it is at today. Now that the balance is being thrown off, it’s time for the seaweed to come and help again.”

The most critical part of the plan is to then convert the seaweed into useful energy — a process that draws on technology produced by the Mitsubishi Research Institute. When blasted with superheated steam, seaweed discharges hydrogen and carbon monoxide gases that can be used to create a biofuel, which, in turn, discharges no extra carbon dioxide when burnt.

“I think the project is entirely viable on the technology side,” Katori Yoshishige, of the Mitsubishi Research Institute, said. “We need to improve methods to generate methanol from seaweed, for example, but I don’t envisage too much difficulty. The biggest challenges at the moment are financial.”

This is not the first time that seaweed has been identified as mankind’s potential saviour. In the 1970s the United States-led Giant Kelp Project failed because it was unclear what to do with all that seaweed once it was hauled back to shore. Now that seaweed can be converted to energy without expensive fermentation, the idea is back on course.

BBC NEWS | Health | Ocean waters yield cancer therapy

BBC NEWS | Health | Ocean waters yield cancer therapy
Les possibilités thérapeutiques qu'offrent les fonds marins sont aussi grandes que celles des forêts tropicales. À l'aide des biotechnologies, si nous réussissons à ne pas tout détruire auparavant, nous pourrions puiser dans ces mines quasi infinies pour le mieux-être de tous les êtres vivants.

Ocean waters yield cancer therapy
Scientists believe they can make cancer drugs from the humble sea squirt.
A microbe that lives within this sea animal produces compounds that may fight some tumours.

Using laboratory techniques they say it should be possible to produce enough of the compounds without having to destroy a large number of sea squirts.

The University of Utah work, funded by the National Science Foundation, is described in Proceedings of the National Academy of Sciences.

Coral reefs and other ocean environments are like rainforests - full of natural chemicals to potentially treat human disease
Researcher Dr Eric Schmidt
Professor Marcel Jaspers, at the University of Aberdeen, along with colleagues from the Australian Institute of Marine Science, have made similar discoveries by looking at the sea squirt.

The Utah researchers discovered that Prochloron microbes, which live inside the sea squirt Lissoclinum patella , produce two compounds called patellamide A and C, which are thought to have anti-cancer properties.

Next, they pinpointed the gene pathways that the microbes used to make these compounds.

Researcher Dr Eric Schmidt said: "Coral reefs and other ocean environments are like rainforests - full of natural chemicals to potentially treat human disease.

"Unfortunately, it's difficult to supply pharmaceuticals from these delicate environments. We have solved this by finding specific genes for the synthesis of chemicals using laboratory bacteria."

Eco-friendly

Their Prochloron genome project - in collaboration with Margo Haygood at the Scripps Institution of Oceanography at the University of California, San Diego - is still under way.

Dr Matthew Fletcher, lecturer in Organic Chemistry at the University of Wales, UK, and member of the Society of Chemical Industry, said: "This is a step forward towards simpler, sustainable methods - using a combination of chemical and microbiological techniques - for the production of "drugs from the deep" that avoid the harvesting and destruction of unsustainably large quantities of marine organisms.

"The marine environment is a realm of biological and chemical diversity, and the marine organisms that live in it are a rich source of intriguing and unusual molecules with the potential to become powerful drugs.

"However, these molecules are usually present in minute quantities in rare organisms.

"So instead of diving for these 'pearls' of great price - ravaging the marine environment - we need to develop sustainable methods for the production of drugs."

BBC NEWS | Science/Nature | Bird song sheds light on learning

BBC NEWS | Science/Nature | Bird song sheds light on learning
Bird song sheds light on learning
Young canaries happily learn songs that sound nothing like their species, but they revert to a strict canary-like melody as they mature, Science reports.
A US team was surprised to find it could teach juvenile birds a haphazard jumble of computer generated tunes.

However, the birds' impressive flexibility gave way to rigid rules when breeding became a priority.

Paradoxically, months of wayward early learning seems to have little impact on the birds' ability to sing properly.

The scientists hope this puzzling course of events will help them understand how birds develop songs.

"The most surprising thing is that the birds were able to imitate, and then paradoxically they abandon this imitation in adulthood," said co-author Tim Gardner, of Rockefeller University, US.
"It seems an excessive capacity for imitation, which is dropped when they grow up."

Copy cats

Young canaries apparently learn their songs by closely copying a nearby adult, a laborious process that usually takes between six to eight months.

In order to test how flexible their approach to learning is, the US team exposed young male canaries to computer generated tunes that did not follow any of the standard canary-song rules.

The team found that the youngsters picked up the foreign tunes and reproduced them with enthusiasm.

But then something rather strange happened. As soon as the canaries received a pubescent surge of testosterone, they dropped all the incorrect lessons they had learned and started singing traditional canary songs.

Even canaries that did not get to imitate any songs at all developed the proper tune as adults.

Counter-intuitively, although they spend a long time labouring over new songs, listening carefully, imitating and perfecting, young canaries do not actually seem to need it. Once adult, they can sing just fine without it.

Free learning

"We don't have a full answer for this," Professor Gardner told the BBC News website. "But birds that go through this period of imitation might have a richer repertoire of syllables so the interaction between this early freedom and the later rules ends up creating a more diverse set of sounds in adulthood."

In other words, although the birds who sang nonsense as juveniles sound perfect to the human ear, they might not sound quite so good to the canary ear.

The real test, according to Professor Gardner, would be whether or not females chose them as mates over birds that grew up with more conventional lessons.

It might seem odd that young canaries are so extremely flexible when they are first imitating sounds, especially since the adult song is pretty rigid, but Professor Gardner believes it could be important.

"It may be that imitation requires this kind of freedom," he said. "The neural pathways involved in learning might actually require that degree of freedom in order to accomplish learning."

From archeology Mensa group - Interesting

I recall lecturing on the evolution of the eye, in which we have living examples of every stage of that evolution. There are phototropic and photophobic single celled organisms wherein the entire surface of the organism is sensitive to light. There are others, more evolved, which have one small area of the cell wall sensitive to light. These swim in spiral pattern, scanning their environment for light sources. In the next step forward, that spot is recessed, enabling a sharper focus. Finally, a protective membrane covers the light sensitive and, becomes a lens, etc., etc. All it takes is sufficient time, the environmental advantage of seeing and individual variation in the ability to detect light and its direction. Given a few billion years and voila, the complex eyes of higher organisms.

Henry Miller

ScienCentral: Virtual Pain Relief

ScienCentral: Virtual Pain Relief
The pain of severe burns may be the most excruciating pain a person can experience. But, as this ScienCentral News video reports, pain researchers say the fantasy worlds of virtual reality can help alleviate the real, physical suffering of burn victims.

Six-year-old Nathan Neisinger suffered serious burns when he accidentally pulled a pot of boiling water onto himself.

"He had third degree burns and they were over 31 percent of his body," says his mother, Heidi. "His whole entire chest, his back, his legs, part of his foot, had third degree burns all over them. They had to do skin grafting; they had to take skin off of his behind, off of the back of his legs."

Besides skin grafts, Nathan has endured months of wound care and more pain than safe doses of narcotics can alleviate. "The care is very often more painful than the injury itself," says David Patterson, a psychologist and pain expert at Harborview Medical Center in Seattle, where Nathan spent 51 days after being airlifted there for his injuries. "Typical care involves removing bandages and then scrubbing the wound, and for some patients, you do that once or twice a day, for days, weeks, and even months."

And then there was the physical therapy to stretch his scarred skin. "The actual process of going through that physical therapy is often very extensive," says Patterson. "You can hear some ripping and cracking. It can be anxiety-producing to anyone, much less a six-year-old."

SnowWorld image: Hunter Hoffman, University of Washington Seattle
But while Nathan's body is put through the wringer, his brain can cool off and play in a 3-D computer-generated environment called "SnowWorld." Patterson and Hunter Hoffman, director of the VR Analgesia Research Center at the University of Washington's Human Interface Technology Laboratory, created SnowWorld, a virtual reality (VR) game, especially for people like Nathan.

"SnowWorld is the first virtual environment that was specifically designed for treating burn patients," explains Hoffman. "We made snowflakes, snowmen, igloos, robots, [and] penguins, and you hear this soothing music. The idea is to help the patients take their mind off of their pain. The nice thing about SnowWorld is, all these images of cold hopefully counteract…the fires of their burn pain."

"What we're really trying to do is just to pull his attention away from what's happening in the therapy, to put his attention in the virtual world, and by virtue of that, have him experience less pain," adds Patterson.

Clinical studies with patients like Nathan are showing how effective virtual reality is at fighting burn pain. In an article in Scientific American, Hoffman described how they used a special virtual reality helmet that would work in a magnetic resonance imaging (MRI) scanner to confirm this. The team studied five regions of the brain that are known to be associated with pain processing. "We found that all five regions showed significant reductions, and the amount of reductions during VR, the amount of reductions in pain-related brain activity, ranged from 50 percent to 97 percent," says Hoffman. "The incoming pain signal is not even being processed during VR. There's much less pain being processed by the brain when the person's in VR."

When they tested SnowWorld against a more typical Nintendo home video game system, the virtual reality experience was much more effective at easing pain. Hoffman says the key to why VR seems to work so well is the feeling the patient has of going inside the computer-generated environment. "The person has the sensation of actually going into SnowWorld. And we've shown that there are correlations…the more they feel like they went into SnowWorld, the more pain reduction they show," he says. "So we're very keen on trying to make virtual worlds that are more convincing, that are more successful at luring the person into the virtual environment."

Heidi Neisinger says she feels lucky that her son gets to experience SnowWorld. "He had to go through a lot of pain which…was really hard on him, but that's where the virtual reality is good, because he was able to put that on and get his mind off of it when he was playing virtual reality," she says. "Your ears also are hearing what virtual reality is going on, they're not hearing the discussion between the nurses and doctors, so that helps a lot—you're not hearing what they're gonna do to you."
In fact, this is really just a high-tech version of an old technique: distraction. "People have used distraction techniques for a long time," says American Pain Society president Dennis Turk. "Virtual reality allows you to get totally immersed, and the more engaged and distracted they are, the higher the benefit will be."

Turk, who is also a professor at University of Washington, says he'd like to see more studies like this one with larger groups of subjects, but that the results confirm what he's felt for a long time: "The mind and the body are integrated, and that's how we need to keep thinking about pain."

Hoffman and Patterson, whose creations are also being used for people with phobias and post-traumatic stress disorder, hope virtual reality will soon be available to help many more patients' brains escape their real pain. This research appears in the August, 2004 issue of Scientific American, and the clinical study was published in the June, 2004 issue of NeuroReport. It was funded by Paul Allen, the co-founder of Microsoft, and the National Institutes of Health. The study comparing SnowWorld to Nintendo appeared in the March 2000 issue of the journal Pain.

Acupuncture: des bienfaits et effets mesurables

Acupuncture: des bienfaits et effets mesurables
Acupuncture: des bénéfices et effets mesurables
Mise à jour le jeudi 5 mai 2005 à 16 h 16

L'acupuncture a bel et bien des effets sur le corps humain. Si cette technique de la médecine traditionnelle chinoise est utilisée depuis des siècles pour traiter les maladies et la douleur, aucune étude n'était jusqu'à maintenant parvenue à montrer scientifiquement ses effets positifs sur la santé. Eh bien, des chercheurs britanniques et américains y sont parvenus.
Une première étude, réalisée par une équipe de l'université du Maryland, montre que la pose d'aiguilles sur des points précis a un effet mesurable et spécifique sur l'activité de certaines zones cérébrales.

Les chercheurs ont utilisé l'imagerie magnétique pour voir les effets de l'acupuncture sur le cerveau de personnes qui souffrent d'arthrite.
Le même exercice a été réalisé avec de fausses aiguilles qui déclenchaient une sensation de piqûre, sans toutefois pénétrer dans la peau.

Les résultats montrent qu'une région du cortex est systématiquement plus activée lors d'une vraie séance d'acupuncture.

Une seconde étude, menée à l'université anglaise de Southampton, montre que l'acupuncture est plus efficace qu'un placebo ou que l'absence de traitement pour soulager les douleurs chroniques associées à la région lombaire.

Cependant, les aiguilles n'ont pas démontré une efficacité supérieure à celle d'autres approches thérapeutiques courantes auxquelles on les avaient comparées, comme la massothérapie et l'exercice.

Emotions et santé - encore...

news @ nature.com�-�Angry heart flutters prove most dangerous�-�Heightened emotion linked to premature cardiac contractions.
Angry heart flutters prove most dangerous

Roxanne Khamsi

Heightened emotion linked to premature cardiac contractions.

The surge of adrenalin from an argument might trigger deadly heart flutters.

Tony Blair may want to stay calm during the British elections: a study of people with cardiac troubles suggests that bursts of anger precede the most dangerous flutters of the heart.

Although Prime Minister Blair has no current heart troubles, he had a procedure to correct an irregular heartbeat in October 2004. The results may also hold true for those with healthy hearts, the researchers say.

To explore how feelings affect heartbeats, Matthew Stopper of the Yale University School of Medicine in New Haven, Connecticut, and his colleagues asked 24 patients with implanted defibrillator devices to keep a diary of their emotions.

The patients all had conditions that can disrupt electrical signals to the heart, causing an unhealthy quivering of the muscles. This in turn can lead to a cardiac arrest. Their implanted defibrillators are designed to detect these abnormalities and deliver a life-saving electric shock to put their hearts back in the right rhythm.

After receiving such a shock, participants in the study rated how angry they had felt beforehand on a scale of 1 to 5.

The medical team then retrieved information from the defibrillator devices to see how their hearts had gone wrong.

Arresting data

Out of the 56 shocks recorded during the study, the researchers found that in 100% of cases where people reported anger levels above 2, the arrhythmias were initiated by a series of rapid, premature heart contractions. This type of contraction is known to put an individual at greater risk of sudden arrest.

In contrast, only 68% of arrhythmias not preceded by angry feeling had this characteristic. Stopper and his fellow scientists presented their results on 5 May, at the Heart Rhythm Society's annual meeting in New Orleans, Louisiana.


"We know that the emotional distress brought on by earthquakes, missile attacks and even the loss of key football matches can trigger heart attacks," says health psychologist Doug Carroll of the University of Birmingham, UK. "It had been presumed that this results from an increased likelihood of clot formation. But this study tells us that strong emotions such as anger can also disrupt the electrical rhythms of the heart."

Stopper's team isn't sure exactly how anger has this effect. But they think that the adrenaline surge associated with a burst of anger might be the trigger.

Darwin doit comparaitre

Darwin comparaitre
Darwin cité à comparaître
Mise à jour le mardi 3 mai 2005 à 10 h 12
Un procès peu commun s'ouvrira jeudi au Kansas. La théorie de l'évolution de Darwin sera au centre d'une cause destinée à déterminer la façon d'enseigner l'apparition de la vie sur Terre aux écoliers.

Pendant six jours, plus d'une vingtaine de témoins seront entendus et contre-interrogés, à la demande du Conseil de l'éducation du Kansas. La majorité d'entre eux devraient plaider contre l'enseignement de la théorie de l'évolution, puisque d'éminents groupes de chercheurs ont annoncé le boycottage des audiences, estimant le débat fondé sur des arguments erronés.
L'avocat Pedro Irigonegaray défendra la validité scientifique de la théorie de l'évolution. Il estime que « remettre en cause l'évolution, c'est comme remettre en cause le fait que la Terre est ronde ».

Il sera opposé à l'avocat John Clavert, directeur général de l'Intelligent Design Network. L'organisation défend l'idée que l'apparition de la vie terrestre est le fruit d'un dessein intentionnel et non de l'évolution aléatoire des espèces.

« Nous ne sommes pas contre l'évolution, explique-t-il. Mais beaucoup d'éléments prouvent que la vie est le fruit d'une intelligence. Je ne crois pas que l'État doive trancher la question de savoir si nous sommes le fruit d'un dessein ou seulement du hasard. »

Au cours des dernières années, de nombreuses associations remettant en cause la théorie de Darwin sont apparues aux États-Unis. Si certaines se réclament du créationnisme, rares sont celles qui vont jusqu'à réclamer l'enseignement du créationnisme à l'école; elles encouragent les enseignants à exposer plusieurs points de vue.

En 1999, le Conseil de l'éducation du Kansas avait voté en faveur d'une minimisation de la théorie de l'évolution dans les cours de sciences. Peu après, des élections ont permis le retour de la théorie de l'évolution dans les écoles en 2001.

Selon la théorie de Darwin, l'espèce humaine descend de singes ayant vécu il y a quelques millions d'années.
Mais les élections de l'an dernier ont redonné la majorité aux conservateurs religieux. Le conseil s'emploie maintenant à rédiger de nouveaux standards scientifiques qui devront guider les professeurs.
La théorie de l'évolution a été élaborée en 1859 par le naturaliste britannique Charles Darwin, dans son essai Sur l'origine des espèces. En 1925, lors d'un célèbre procès, un professeur du Tennessee a été condamné pour avoir enseigné les thèses darwinistes à ses élèves.

Les détracteurs de la théorie de Darwin soutiennent qu'elle est incompatible avec la Bible, qui dit que Dieu a créé la vie sur Terre, ainsi que les deux premiers humains, Adam et Ève, en six jours. Ses défenseurs rétorquent que la théorie de l'évolution procure des fondements scientifiques nécessaires à la compréhension de la génétique et de la biologie moléculaire.

'TM can reduce death rates'

'TM can reduce death rates'
'TM can reduce death rates'

Transcendental Meditation (TM), a non-drug relaxation or stress-reduction method, reduces death rates by 23% and extends lifespan in the elderly, according to a study published in the American Journal of Cardiology.

Researchers evaluated 202 men and women aged at 71 on average with mildly elevated blood pressure.

The study found that compared to control groups, the TM group showed:

• 23% reduction in the rate of death from all causes;

• 30% reduction in the rate of death from cardiovascular disease;

• 49% reduction in the rate of death from cancer.

"Research has found the transcendental meditation programme reduces risk factors in heart disease and other chronic disorders, such as high blood pressure, smoking, psychological stress, stress hormones, harmful cholesterol, and atherosclerosis," said Dr Robert Schneider, principal author of the study and director of the Center of Natural Medicine and Prevention.

"These reductions slow the aging process and promote the long-term reductions in death rates."

The study was conducted by researchers from Harvard, University of Iowa, Medical College of Georgia, West Oakland Health Center, and Maharishi University of Management.